Method and apparatus for making spring motors



H. L. PITMAN.

METHOD ND APPARATUS FOR MAKING SPRING MOTORS.

APPLICATlON FILED JAN- 30. 9]9.

Patented Nov. 28, 1922..

2 SHEETS-SHEET l.

H. L. PITMAN. METHOD AND APPARATUS FOR MAKING, SPRING MOTORS.

, APPLICATION FILED IAN-30,1919. 1,436,678.

2 SHEETS-SHEET 2.

Patented Nov. 28, 1922.

NEE

Patented Nov. 28, 1922.

HENRY I..'PITMAI\T, 0F ELIZABETH, NEWJERSEY.

METHODAND APPARATUS FOR IJIAKING SPRING MOTORS.

Application filed January 30, 1919. Serial No. 273,977.

To all whom it may concern:

Be it known that I, HENRY L. PITMA'N, a citizen of the United States, residing in Elizabeth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Method and Apparatus for Making Spring Motors, of which the following is a specification.

This invention relates to coiled motor springs of extraordinary length and capable of exerting prolonged driving power before requiring to be rewound, and useful especially for driving the record-carrying tables of phonographs.

An object of the invention is to produce at low cost a compact, reliable, practicable, noiseless and durable spring of this character.

.ln winding a helical spring, and continuing the winding to form a helix running back over the first helix, the outer helix would not wind evenly, unless square wire were used, since in some places, if it were attempted to use round wire, the outer wire would sink into the hollows between the whorls of the inner helix, and hence become permanently depressed, while at other places, the outer windings would ride upon the inner whorls, and hence become permanently elevated, so that the form of the outer helix would be irregular. Moreover, unless great care were used, one or some of the outer windings would be apt to crowd their way down and force. apart the inner whorls, thus rendering the spring defective.

Another objection if it were attempted to use the spring for a phonograph, would arise from the noise due to the scraping of outer whorls over the inner whorls. This would be due to a relative bodily movement or creeping of the whorls of the outer helix in axial direction. This will be clear when it is borne in mind thatin rewinding such a spring, each revolution would add a whorl to the outer spring, and that more whorls would be added to the outer helix than to the inner helix. In'other words, the outer helix would lengthei'i more than would the inner helix. During such relative creeping of the outer and inner whorls, they would be apt to rub upon one another and produce an objectionable grating sound; and the liability of. this objection would be great because of the unevenness in the forms of the outer whorls due to causes already explained. This objection would be prohibitive for phonographs, in which it is customary to rewind the motor spring while the instrument is playing.

Another objection to such an unevenly formed spring would be that the outer and inner whorls would scrape the lubricant off from one another, to the detriment of the action of the spring.

One of the objects of the invention is to overcome the aforesaid objections, so that a round wire may be employed, the same being well adapted for use in this class of springs, as it is relatively inexpensive and reliable, and capable of substantially uniform and accurate tempering. Ipreferably employ the so-called music wire for this purpose, which is procurable in its finally tempered condition, and is capable of being wound into an eiiicient spring, without subsequent application of heat or other treatment.

In order to overcome the aforesaid objections, I make the outer helix'core-wound, that is, I wind the outer helix upon a core instead of winding it upon the inner helix, as heretofore proposed. 'The outer helix being thus wound, is evenly formed, and none of the objections above-mentioned arise. The core for the outer helix is a smooth cylinder, in order to secure the same evenness of winding as is common in a single helix.

An objection to the use of a long spring consisting of a single helix, or even of a single helix overwound by another helix, would reside in the necessarily excessive bodily length in either case, making it prohibitive for use in phonographs, where compactness is a necessity, especially where it is desired to produce a driving motor and equipmentsuitable for use in any of a large variety of styles of phonographs.

In order to overcome this objection and secure the desired compactness, and at the same time greatly lengthen or prolong the driving action of the spring, I first wind an innermost helix, which may be short as compared with previous springs, and then form over that a core-wound second helix, and then form over the second a core-wound third helix, and then form over the third helix a core-wound fourth helix. The bodily length of the spring may, therefore, be very much less than would be the case with a spring consisting of only a single or double helix, thus securing necessary compactness; while the-core-winding makes it feasible to porary sixth add the third and fourth helices, which otherwise would be too irregular in form for .manufacturing and practicable purposes; since the great irregularity of the second helix (if wound directly upon the first), would be multiplied in the third helix, since the winding of the third helix upon the irregular second helix would result in much more uneveness than the winding of the second helix upon the first helix; and the winding of the fourth helix directly upon such extremely uneven and irregular third helix would result in a monstrosity, and be impracticable.

If desired, according to my invention, the winding may be continued beyond the fourth helix, thereby forming afifth core-wound helix; and even a sixth core-wound helix may be formed over the fifth in some cases.

In making the spring described herein and illustrated in the drawings, and also illustrated in my pending applications 149,855, 193,138, and 269,311, I wind the first or inner helix upon a temporary core in a lathe, and then, while said helix remains under tension, I enclose the same in a temporary second core, wh ch is in the nature of a shell, tube, or sleeve, which, for convenience in slipping upon the helix, may have a slit extending from end to end, so that it may be slipped endwise upon the helix, the slit permitting the core to slip past the unwound end of the wire. The core may be made of very thin metal, and, if desired, may be opened out sufficiently to slip it over the body of the helix to clasp upon the same.

Thereupon I wind the second helix back over said second core. The windings tend to close the slit in the core, and the core serves to bridge the crevices between the whorls of the first helix, whereby the windings of the second helix are rendered smooth and even, as if they had been. wound upon a solid cylinder.

After completing the winding of the second helix, I slip thereover a temporary third core, also in the form of a longitudinally slitted thin tube or shell, which may be opened out to slip bodily over and clasp upon the second helix; and then I proceed to wind the third helix forwardly over said third core. Having completed the winding of the third helix, I place thereover a temporary fourth core, also in the'form of a slitted sleeve or shell, of the required diameter, and wind back thereon the fourth helix. All of the whorls in all of the helices are even and regular. If a fifth helix is to be wound, a temporary fifth core may be used; and if a sixth helix is to be wound, a temcore may be used.

After winding the spring in the aforesaid manner, the same ispermitted to expand or relax, the helices shortening in length and The shells or cores enlarging in diameter.

for use 1n windmay be slipped off endwise, ing more springs.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure 1 is a plan of a lathe, showing the manner of win'ding'the innermost helix.

Figure 2 is an elevation of the face plate, seen at the left hand of Figure 3.

Figure 3 shows the completion of the winding of the innermost helix, whose beginning is seen at Figure 1.

Figure 4 shows in elevation the righthand face plate, seen at Figure 3, also in section the slide rest carrying the wire guide.

Figure 5 illustrates the second core forming a jacket upon the first helix, preparatory to winding back the second helix.

Figure 6 is a perspective of the second core seen at Figure 5.

Figure 7 is a fragmentary perspective to illustrate the arrangement of the cutaway or notch in the end of the second core, as it clears the length of wire which extends up from the first helix to begin the winding of the second helix.

Figure 8 shows the completion of the winding of the second helix back over the first.

Figure 9 is a perspective view of one end. of the third core, adapted to slip or clasp over the second helix.

Figure 10 shows the completion of the winding of the third helix forwardly over the third core; a portion of the windings or whorls being broken away to disclose the third core.

Figure 11 is an end view showing the connecting whorl between the second and third helices.

Figure 12.is a perspective view of a portion of the fourth core for clasping over the third helix.

Figure 1.3 illustrates the completion of the winding of the fourth helix.

Figures 14: and 15 are end views showing the connecting whorls between the various helices.

Figure 16 is a sectional View to illustrate various features of the assemblage seen at Figure 13.

In practicing the novel method of winding the novel spring, the round piano or music wire 20 (or other spring wire) for forming the spring, is led through a guide block 21 provided upon the slide rest 22 of a lathe 23, and is caught in a hole 2i provided upon a face plate 25 connected to the driving spindle 26 of the lathe, and secured by a set screw 27. Also connected to said driving spindle is a cylindrical core 28, which, at its other end, is supported upon the tail stock '29 of the lathe. The

lathe is started, and the slide rest is fed along preferably by an ordinary screw feed 30, as the wire 20 winds upon the core 28 to form the innermost helix 31 of the spring.

As soon as this first helix has been wound, the lathe is stopped, and the helix in its tense condition is jacketed by a sleeve or hollow core 32 of thin sheet steel. This core 32, which forms the second of the coresemployed in building up the spring, is provided with a slit 33 extending from end to end, and the core may be opened out sufficiently to enable it to he slipped over the first helix 31. Another way to place the core or sleeve would be to remove the tail stock 29 and the right-hand face plate 34, (secured by a set screw 34 to the core 28), and slip the core 32 endwise over the helix, the slit 33 being presented to the unwound portion 33 of the wire, which extends from the helix to the guiding block or head 21, so that said unwound portion will not present an obstruction to the slipping of the core over the helix, since the core 32 may readily be sprung open sufliciently to accommodate this wire. The face plate 34 and the tail stock 29 may then be returned to position, preparatory to winding the next outer or second helix. The right-hand cnd of the core or jacket 32 is notched or cut away at. 5 to form a clearance for the portion33" of the wire which extends out from the end of the first helix to begin the wind ing of the second helix, and serves to form the connecting whorl 36 between these helices, as at Figure 14. The length of the core or jacket is coextensive withthe length of said inner helix, forming a smooth cylindrical body upon which to wind the second helix.

The lathe is again started in motion, and the wire-guiding slide rest 22is fed backw-ardly, or from right to left, as the Winding of the helix progresses; this feeding beingcffected by reversing the screw feed 30 in the usual manner; although it is obvious that the feeding of the slide rest in either direction may be effected by handif desired.

After the completion of. the winding of the second helix 36, which will be formed with even whorls and without distortion, another jacket or sleeve 37 is slipped over the second helix to form a third core, upon which to wind the third helix. This core 37 has a longitudinal slit 38 to permit it to be opened out for slipping over the second helix 36, and also has at its left-hand end a notch or cutaway 39 to clear the portion or whorl 40 of the wire which extends outwardly from the second helix to begin the winding of the third helix 41.

To wind the third helix 41, the feed screw 30 is reversed to carry the slide rest 22 to the right, and the winding proceeds in the same directions until the helix is finished,

whereupon a third sleeve42, having a longi+ tudinal slit 43 and notch 44 at its righthand end, is slipped over the third helix to form a fourth core for the winding of the fourth helix 45, the connecting whorl'46, between the third and fourth-helices, lying in the notch 44.

Although a spring having fifth and sixth helices is not illustrated, still it will be understood from the foregoing that a fourth sleeve may he slipped over the fourth helix to form a fifth core, upon which to wind the fifth helix, and that a sleeve may be slipped over the latter to form a sixth core for the sixth helix.

After the completion of the winding, the spring is permitted to relax, the coils expanding and the helices shortening. The sleeves or hollow cores may now be withdrawn endwise, the slit in each core permitting it to pass the connecting whorl of wire. Preferably the sleeves may be withdrawn at the open ends of their respective helices, as at Figure 16.

Thus there produced a multiple helix spring of very great. length, and capable of an extraordinarily prolonged drive without rewinding, while the tension upon the spring does not seriously vary during the driving of a mechanism core-wound condition of the coils or whorls, the same are even and therefore not apt to sag or spring into contact. with one another, that is, the whorls of one helix are not apt to interfere with the whorls of an (other helix, and the spring may be wound until the several helices are nearly in contact with one another, without noise arising from the contact of any whorl with an adjacent inner. or outer whorl. Thus the spring is noiseless, which is an important advantage in driving phonograph record tables. Moreover the lubricant, which may be supplied to the spring, is not liable to be scraped off by the action of any of the whorls of one helix working along over the whorls of the next inner helix. The spring is compact, reliable and durable, andis inexpensively made as compared with other springs commonly used for driving phonograph tables, etc.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

.1. The method of forming a continuous wire spring comprising separated expand ing helices one within another, said method comprising the steps of winding an inner helix of spring wire upon a temporary core, enclosing said inner helix in a jacket to form a temporary second core, and continuing the winding upon said second core to form an outer helix.

thereby. Owing to the w wire spring comprising 2. The method of forming a continuous Wire spring comprising separated expanding helices one within another, said method comprising the steps of winding an inner helix of spring wire upon a core, enclosing said inner helix in a jacket to form a second core, continuing the winding upon said second core to form an outer helix, and then removing said cores.

The method of forming a continuous separated expanding helices one within another, said method comprising the steps of winding an inner helix of spring wire upon a temporary core, enclosing said inner helix in a jacket to form a temporary second core, continuing the winding upon said second core to form an outer helix. enclosing the second helix in a jaclret to form a temporary third core, and continuing the winding to form a third helix upon said third core.

e. The method of forming a continuous wire spring comprising separated expanding helices one within another, said method comprising the steps of winding an inner helix of spring wire upon a temporary core, enclosing said inner helix in a jacket to form a temporary second core, continuing the winding upon said second core to form an outer helix, enclosing the second helix in a jacket to form a temporary third core, continuing the winding to form a third helix upon said third core, enclosing the third helix in a jacket to form a temporary fourth core, and continuing the winding upon said fourth core to form a fourth helix.

5. The method of forming a continuous wire spring comprising separated expanding helices one within another, said method comprising the steps of winding an inner helix of spring wire upon a temporary core, placing a slit-ted or divided sleeve upon said helix to form a temporary second core, and continuing the winding to form a helix upon said second core.

6. An apparatus for the production of the described spring. comprising a temporary core upon. which to wind an inner helix, and a temporary hollow core to fit upon and be supported: by said inner helix to wind an outer helix thereon.

7. An apparatus for the production of the described spring, comprising a temporary core upon which to wind an inner helix, a temporary hollow core capable of being fitted upon said inner helix to wind an outer helix thereon, and a temporary third core in the form of a sleeve to be fitted over the second helix to wind a third helix thereon.

8. An apparatus for the production of the described spring, comprising a temporary core upon which to Wind an inner expanding helix, a temporary hollow core capable of being fitted upon said inner helix to wind an outer expanding helix thereon, a temporary third core in the form'of a sleeve to be fitted over the second helix to wind a third expanding helix thereon, and a temporary fourth core in the form of a sleeve to be fitted over said third helix to wind a fourth expanding helix thereon.

9. An apparatus for forming the hereindescrihed spring composed of helices, comprising a driving spindle, opposite face plates, a temporary central core, a slide rest having a wire guide, and a sleeve with which to surround the first helix to be supported thereby to form a temporary core for winding the second helix thereon.

10. An apparatus for forming the hereindescribed spring, comprising a driving spindle, opposite face plates, a central core, a slide rest having a wire guide, and a plurality of sleeves of graduated sizes to slip over the helices seriatim as they are completed, for the purpose of forming temporary cores.

11. A flexible metal sleeve slitted from end to end and forming a temporary removable tool for placing over a helix to be supported thereby to serve as a temporary core for winding another helix thereon.

12. A slitted flexible sleeve for placing over a helix to serve as a temporary core for winding another helix thereon; and having at one end a notch or cutaway to clear the connecting whorl between the helices.

13. A slitted flexible sleeve for placing over a helix to serve as a temporary core for winding another helix thereon, and having at one end a notch or cutaway to clear the connecting whorl between the helices, said sleeve being of thin metal capable of opening at its slit to slip transversely over the helix which it is to clasp.

141-. An apparatus for the production 05 the described spring, comprising a temporary hollow core to place upon and be supported by a helix to wind an outer helix thereon, and another temporary core in the form of a hollow sleeve to place over and be supported by the second helix to wind a third helix thereon.

15. An apparatus for the production of the described spring, comprising a temporary hollow core to place upon and be supported by a helix to wind an outer helix thereon, another temporary core in the form of a hollow sleeve to place over and be supported by the second helix to wind a third helix thereon, and an additional temporary core in the form of a hollow sleeve to place upon and be supported by said third helix to wind a fourth helix thereon.

HENRY L. PITMAN.

Witnesses:

CATHERINE A. NEWELL, EDITH B. LIBBEY. 

